[jbent91]

hi i have a 99 malibu 4 cyl i been having my battery light come on while driving the other day i took the altonator ofrf and it was melted where wire bolts on too so i put a new alt on and the battery light is still on and my stereo turned off on me can anyone assist me in this dilema please...

 

[Starship]

By the "melted where wire bolts on" statement, it sounds like there was a short. Go over the charging circuit diagram at http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va115650.pdf and check the wiring and fuses.

 

[jbent91]

i already have all the fuses are good and i ran thru the wiring all checks out to be fine

 

[Starship]

Did you check the fusible link as well? Then, measure the voltage across the battery with the motor off and then with it running (1500-2000 RPMs). With the motor running, the voltage should be .5-2.5 volts above the baseline. If not, you may have a defective alternator or you may have fried the PCM circuit(s).

The way it works, the L Control circuit on the PCM tells the regulator to turn on. The regulator then has to see the reference voltage through the Generator fuse to control the generator. When there's a problem, the regulator grounds the F Input circuit to the PCM which then turns on the battery warning light. There's a lot going on here and thus, if everything checks out as far as you can tell, you may want to consider taking it to a shop.

 

[jbent91]

alright ill check that out to thank you